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Implement _.compact — remove falsy values

Q: Implement _.compact — remove falsy values

**Approach:** `filter(Boolean)` — but be explicit for interview. ```javascript function compact(array) { return array.filter(Boolean); } function compactVerbose(arr) { return arr.filter(v => !!v); } // Demo console.log(compact([0,1,false,2,'',3,null,undefined,NaN,4])); // [1,2,3,4] console.log(compact([0, '', null])); // [] console.log(compact([1,2,3])); // [1,2,3] ``` Used for cleaning API responses with empty slots.

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Understand the problem

Create compact(array) that removes all falsy values (false, 0, "", null, undefined, NaN) from array.

arraycompactfalsy

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Study the solution

Approach: filter(Boolean) — but be explicit for interview.

function compact(array) { return array.filter(Boolean); }
function compactVerbose(arr) { return arr.filter(v => !!v); }

// Demo
console.log(compact([0,1,false,2,'',3,null,undefined,NaN,4])); // [1,2,3,4]
console.log(compact([0, '', null]))

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